Listen is described as 'gives you a smart, free phone number that lets you control when and how you’re contacted while working just as comfortably as a regular phone number. With Listen you can set auto-responses so contacts know when you’re away from your phone' and is an app in the Social & Communications category. There are three alternatives to Listen for a variety of platforms, including iPhone, iPad, Android, Android Tablet and Mac. The best alternative is Phoner Second Phone Number, which is free. Other great apps like Listen are Line2 (Paid) and Ring4 (Freemium).
Phoner provides business owner, sales people, lawyers, doctors, police officers and others with a second phone number to protect their identity and also gives the convenience of multiple phone numbers on one device.
Line2 is a VoIP phone service that lets you call & text from a separate phone number via WiFi or 3G/4G/LTE. At a small premium, Text & call ANYONE in the US/Canada, forwarding & more. Pick any phone number.